At Unilever's Hamburg headquarters, sustainability is a side effect

On Hamburg's waterfront, world-class sustainable architecture has emerged not from lofty green goals but from practical questions like this one: How do you build an office so comfortable that employees want to linger together there?

GREEN-COLLAR WORK: Employees at Unilever's European headquarters meet in one of the building's many unique 'spatial experiences.' (Photo: Chris Turner)

Here's a German story about motivation, intent and sustainability. It's in three parts — you're reading Part One — and it's set in Hamburg, a city that is unfortunately best known outside Germany as the place where the Beatles cut their chops and as the home of the Reeperbahn, one of Europe's best known red-light districts. In reality, it's a lovely and prosperous city, sophisticated and bustling, and by rights it should now be best known as one of the world's premier sustainability laboratories.

What's truly remarkable about Hamburg-style sustainability is how little posturing it does. It doesn't tell you how grand and lofty are its goals, how virtuous its intentions. It simply is. Indeed half the time the sustainable part has emerged naturally — almost accidentally — out of the pursuit of other goals. My first case in point is a startlingly ambitious green building down on Hamburg's waterfront that serves as the European headquarters of the consumer-goods giant Unilever.

Now, when Unilever set out the design parameters for the new building, it was quite clear what its top priority was: it wanted an open, welcoming space that encouraged communication and collaboration among its 1,200 occupants. More to the point, the company wanted something categorically different from the traditional high-rise where it was previously headquartered — a space where, as one Unilever official put it, "an employee on floor 17 did not communicate with someone on floor 12."

The world-renowned firm Behnisch Architekten got the commission to build the headquarters, and between their longstanding bent for efficient design and Germany's high standards for sustainable construction, the resulting building couldn't help but be greener than the average office block. But what's interesting about the resulting edifice, known as Unilever Haus, is how it came to be not just better than average but a world-class green building.

The most distinctive thing about Unilever Haus from the outside is the foil skin that envelops the entire building, and the story of its provenance is characteristic of the way the company's goal of openness was put in the service of sustainability.

Unilever wanted an open, airy interior; Behnisch was aiming to maximize passive solar design elements, heating and cooling and lighting that interior with as much natural sunlight as possible. The typical way to meet Unilever's goal without creating a blinding overheated space would be to use heavily glazed glass, which blocks out solar heat (and is thus inefficient in winter); the typical alternative would be a pricey double-layered façade, with an exterior skin that trapped and routed solar heat and an interior layer to block out the light.

Behnisch, though, came up with its own innovative approach, a two-layered skin for the building that combines the very old and very new, as sustainable design so often does. The very old: "operable windows" (aka windows you can open and close from inside to control the temperature) and Venetian blinds. The trouble with the blinds, though, is that they couldn't handle the high winds of Hamburg's docks, which brings us to the very new solution: the semi-transparent foil wrapper that gives Unilever Haus its distinct look, a high-tech material called ethylene tetrafluoroethylene (ETFE) that lets through all the sun the building needs while shielding the blinds from the wind. In pursuit of a bright, open interior, then, Unilever found itself with a groundbreaking, hyper-efficient new approach to passive solar design.

As for those interiors, they are stunning on many fronts. Here's the soaring main atrium around which the whole building is organized:

This is the sort of inviting, connecting central space Unilever had asked for. It's also the core of the first office building on the planet to be entirely lit by hyper-efficient LED lighting. Not that it needs much artificial light: that big, overhanging hoop is a solar reflector, designed to bring sunlight to every nook and cranny of the atrium.

The whole building is also naturally ventilated and green-roofed, which together with the passive solar elements and LED lights and reflectors have reduced the overall energy requirement to 70 percent below the German average. Every building material was chosen with the best of environmental and human health in mind — not just to be kind to the planet and its people, but also to improve productivity and reduce sick days (which have plummeted among Unilever's staff since they moved in).

For Unilever, all of this was first and foremost a question of profitability: employees who could come to work more often and interact more efficiently while they were there would be good for the company's bottom line. Hochtief, the building's developer, simply presented Behnisch with a budget and a design brief to Unilever's pragmatic specs. It was Behnisch that filtered these goals through a lens of sustainability, sacrificing high-end amenities (expensive fittings and trim, grandiose entryways and office spaces) in favor of a hyper-efficient and ultra-welcoming physical space.

"I consider it not being worth it to talk about an office in terms of function," Behnisch partner Martin Haas told me. "Let's talk about living space. Let's consider well-being as much as possible."

In particular, the Behnisch folks focused on the idea of lingering, creating spaces that workers would naturally choose to hang out and interact and trade ideas in. "The aim in the building," Haas said, "was to create a 'not an office' building. To develop public space, a space to meet."

This sounds like run-of-the-mill management buzzword bingo, but at Unilever Haus, there's evidence of the real thing everywhere:

The scene above wasn't staged. The photo was taken late afternoon on a rainy spring weekday, the kind of grey day where you're inclined to spend your last hour or so at work daydreaming or surfing the net. But there are Unilever's employees, lingering in the meeting spaces Behnisch designed.

Behnisch's Martin Haas told me they had begun from the idea that people spend as many of their waking hours in their office building as they do at home, so the place needed to be not a work space but a living space for working in, "a little village" with many different kinds of "spatial experiences" for all the different moods of the working day.

Somewhere in all of this talk, you'll find the idea of sustainability. To create a great environment for working in, you have to make the air quality superlative, give it lots of natural light, make it comfortable and efficient, place it in a vibrant community where there's lots to do before and after work and on lunch hours, make it easy to get to and from. The foundations of all of this are sustainable foundations. Sometimes, though, they're no more visible than a building's framework is as you ponder its striking foil-wrapped façade. To get to exemplary sustainability, in other words, you can start with something as simple as making an office space work better.

To marvel at green design 140 characters at a time, follow me on Twitter: @theturner.